An emergency call is a connection from a communication terminal, mostly to an emergency call center, in order to raise the alarm in an emergency at a professional service such as a rescue service, fire service or the police. Special emergency terminals (known as emergency telephones) but also normal wired or wireless communication terminals can be used for this purpose.
The emergency call center can be a factory security center or a public emergency call center for example. This emergency call center accepts the emergency call of the communication terminal and processes said call. Usually the emergency call center asks for the following information in such cases:
Where is the emergency occurring?
What has happened?
How many people are affected?
What type of emergency has occurred?
Further information, such as the time of the emergency call, the identity of the caller and the telephone number of the communication terminal making the emergency call and such like is also recorded in these cases.
If the emergency call is made for example from a public telephone or from a mobile telephone in many cases an automatic, but mostly imprecise, determination of the position of the communication terminal making the emergency call is possible.
Thus in the case of an emergency call from a mobile telephone it is possible for the emergency call center to roughly identify the approximate position of the mobile telephone with the aid of information of the mobile radio network operator. This is done by the base station from which the mobile telephone has established the connection to the mobile radio network being determined. Its precise location is then known. Since the accuracy of the positioning depends on the size of the radio cell of the mobile radio network covered by the base station, the location of the mobile telephone making the emergency call can only be established in towns with an inaccuracy of 100 m to 1600 m, and in the countryside with an inaccuracy of up to 24 km. This merely enables it to be determined whether a mobile telephone is located in a radio cell, but not whereabouts in a radio cell the mobile telephone is precisely located.
In the case of an emergency call from a public telephone network its position can sometimes be determined by interrogating a database in which position information of the public telephone network is stored. The same applies to an emergency call made from a communication terminal within a non-public communication network, e.g. a corporate communication network. Here too it is possible to operate such a database and thus determine the position of the communication terminal making the emergency call. As a rule the information stored in such a database is permanently-stored or static position information.
However for effective emergency management by the emergency call center the most up-to-date determination of the location of the emergency call is of decisive importance, to enable correspondingly current accurate and comprehensive information to be transmitted to the rescue workers.
However the information available to the emergency call center and the rescue workers largely relates to the static position information just described from such a database and to the additional information that the person making the emergency call can supply on request via their communication terminal to the emergency call center.
Frequently there is also no further information available to the emergency call center. This means that the center is restricted to this information as a basis for deciding on a rescue deployment, planning and executing it.
Publication DE 102 54 623 A1 discloses a mobile terminal, as well as an emergency call communication system in which, for an emergency call from a mobile communication terminal in a mobile radio network, the selection of the rescue control center to which the emergency call is directed is made depending on the data provided by the mobile radio network characterizing the approximate location area of the mobile communication terminal.